Drilling machine



' ward stroke of the 'piston results from the -cam action between the grooves l5 and lugs 16, the chuck being prevented from rotating lin the reverse direction in cases where the Y eration.

Vdrag von the drill steel would not prevent this by means of its pawls and ratchet. When the piston reaches the front end of its strolte it is rotating rapidly, and the chuck, if it is under much load opposing rotation, as will normally be the case, will be stationary. The direction of rotation of the piston on the forward stroke is that in'whichit causes "the chuck to rotate on the rearward stroke,

and when the piston is .at the point of reversal at the'end of the forward stroke it isr rotating most rapidly and would continue to rotate in the same direction on the rearward stroke were it not that the action of the grooves l5' and lugs 16 connecting` the piston to the ycl'uiclrtends to cause the piston torotate in the opposite direction as it moves rearward, it being observed that it is this action of the groovesV l5 and lugs 16 that causes the ratchet ring'12 to operate on the rearwardstrolre to hold the piston from rotation in the direction opposite that under consid- The chuck therefore, through the grooves l5 and lugs 16, ator just after reversal of the piston, absorbs the rotative energy ofthe piston which aidsv the chuck in rotating.l ,As the piston reversesV in a small fraction of a second the absorbing of the rotative energy ofthe pistonby the vchuck is done almost instantly and results in a hammer blow ina rotary sense being imparted to the chuck, whichis of great value when the drill tends to stiel; in the drillhole. lt will be observed therefore that the piston on the forward stroke is caused to rotate and that when itreverses the energy of this rotation yis imparted to the chuck, further rotation being imparted to the chuck due to the slip joint connections as the piston continues its rearward motion. Y

rlhe rear hea-d structure comprises a handle member 22 and the valve 'casing comprising the blocks 23 and 24e. Formed with the valve block 24 is a motive fluid connection 25 from which leads a passage`26 adapted to be controlled by a valve for supplying the motive iluid to the opposite endsof the cylinder. Leading from the forward end of the cylinder is a passage 28 which communicates with the passage 26'tl1rough a port 29. Commu- Vitsy weight and inertia.

is clearly illustrated bythe drawings are arranged in opposedspaced relation. Between the ports is mounted a valve 33 provided with opposed spherical faces 3e and 35 which are adapted tov seat onthe surface of the blocks about the ports 29 and 32. This valve l preferably malte hollow in order to reduce Connected to the valve is a flexible stem 36 and on the end of the stemopposite the valve is secured a trunnion 37 which is preferably spherical in order to provide a universal mounting for the valve so that the latter may readily adapt itself to its seat. rlChe blocks 23 and 2st are respectively provided with semisphericalbearings 38 and 39 conforming to the shape ofthe spherical trunnion 37. The valve stem 36 is erforated at lOand extendingthrough such perforation is a pin il of smaller diameter than the perforation serving to hold the valve in operative relation to its seats. `'lhe pin 4l further serves as a dowel to hold the blocltsy 23 and 2d in alignmont.

For exhaust-ing the motive fluid from the opposite ends of the cylinder is a passage 42 leading to the atmosphere and communicating with the interior of the cylinder through. a passage 43. The passage Il?) is adapted to be uncovered by the .forward and rearward ends of the piston in its reciprocation to eX- haustthe motive fluid from in front and behind the piston. v

The operation of the vvalve mechanism is as follows: VAssume the motive fluid supply is communication with the connection Under thesev conditions, if the parts are in the position illustrated by Fig.' 29 the motive fluid is flowing into the rear end of the cylinder through the port 32 and passages 3l and 30. rlhis has driven the piston from its Vrearward to its forward end and with the fluid 1s VYdischanging to the atmosphere through the passage 4:2 and the motive fluid which has'been trapped in the forward end of the piston is exerting pressure on the spherical face 3.1i of the valve. The dis charge of motive fluidto the exhaust through the passage 4:2 relieves the pressure on the rearward face '35 of the valve which permits the pressure acting on the opposite face Sei to shift the valve to the rear, closing the port 32'and opening 'the port- 29. The motive fluid now flows through theport 29 and passage 28 to the forward end'of the cylinder, the motive fluid in the rear end of the cylinder continuing to exhaust through. the

Vpassage 42. This moves the piston rearwardly. After the pist-on in its rearward; strolre closes the passage 43, it traps and compresses fluid in front of itv and this iiuid acting through thepassages and 31 on the rearward face of the valve tends Vto balance the pressure exerted on the for- Ward face 34 of the valve and as soon as the forward edge of the piston uncovers the port 43 vand exhaust fluid from behind it to the atmosphere, the pressure on the surface 34 of the valve is relieved sufficiently to allow the pressure on the opposite surface 35 to throw the valve again to the position shown by Fig. 2. The operation is now repeated.

In order that the piston may operate the drill steel by impact and rotation, the latter is held in operative relation to the piston and chuck by means of a suitable tool retainer. This retainer comprises a yoke portion 44 adapted to engage the collar 45 of the drill steel and formed therewith are the rearwardly extending members 47 and 48. The portion 47 of the retainer is bent to form the trunnion 49 andthe portion 48 bent to form a similar' trunnion 58. Extending rearwardly from the portion `forming the trunnion 58 is a portion 59 bent to form a suitable handle member GO. For supporting the trunnions of the yoke I preferably form the ends of the side rods 61 and 62 ith eyes 63, the rod forming the yoke being bent on arcs of suiicient radius to allmv'thev yoke to be threaded through the eye of the side rod adjacent the handle of the yoke.

The portions of the front head adjacent the eyes are cut away to form the shoulders 65 and 66, conforming to the shape of the eyed portions of the side rods and thus holding the eyes in aligned relation and preventingthe side rods from turning.

To lock the handle in position I provide at the side of the casing lforming the front head structure7 lugs 67and 67, the portion between the lugs being recessed'as at 68 to conform with the exterior surfaceo-f the handle. As the handle is resilient When the same is forced over the member 66, it snaps into engagement with the recess 68 Awhich holds the handle from moving from position until it is forcibly removed from the recesses. In order to prevent harmful vibration of the yoke, which Would tend to cause Wear in the eyes and trunnions I preferably form the lugs 67 and G7 and the recess 68 so that the handle portion 69 is continually under fleXure. This provides a resilient means Which tilts the yoke and causes it to bind in the eyes, the truunion 58 binding against the surface A of the eye and the truunion 49 against the surface B.

The side rods 6l and G2 extend rearwardlyv of the casing and project from the handle member Where they are provided with nuts TO, the cylinder member and head structure being provided with openings to receive the v bolts and the Walls of these openings being `tion relatively to said casing7 a contracted at the portions 7l. 7 2, 73,74 and y75 thereof to tightly engage .the bolts in order -thatthe latter may act 'as dowels to hold :the parts in assembled angular relation.

The pawls her'einbefore referred to are provided with hub portions 76 surrounding the side bolts. A .double bearing for the paivls is prnvided by permitting the exterior i surface 77 of the hub to bear on the casing j and the interior surface 78 to bear on thevside bolts. It will be understood in devices of this character, the paWls are subject to con- -siderable Wear and by thus arranging the parts, the bearing surfaces of the pavvls are considerably increasedl and their life prolonged. i Y

It will be observedthat I have provided a machine in which the casing containing the mechanism for operating .the drill lsteel and the mechanism for retaining the .drill steel in position to be so operated are all heldin assembled relation by means 'of the side bolt-s. Although I'have described one specific em` bodiment of my invention for illustrative purposes,y it is to be understood that I am not limited thereto and that extensive deviations may be made therefrom Without departing from the spirit of my invention.

' Claimszi l. A drilling machine having in combination, a casing, la hammer pistou in said ing, a. chuck mounted for rotation in said casing, means for rotating said piston on its strokes in one direction Without enforcing rotation of rsaid chuck and imparting the energy of such rotation to said chuck vafter completion of sai'dstrokes, and means causing said piston to enforce rotation ot said `chuck on its strokes inthe oppositedirection;

2. A drilling machinehaving in coinbination, a 'casing containing a reciprocatoyy hammer piston, a chuck moi'inted'for rota- Y slip joint connection between said piston and chuck, a inen'iber hayinga slip joint connection with said piston and a ratchet lconnection ijvili said casing' pern'iittingsaid piston to rc in the same directionk as said chuck. said slip joint connections each comprising affini the tion relatively to said casing and having a chuck, a member having4 a lslip jointV Connection with said piston and a ratchet connection With said casing permitting said piston to rotate in the same direction assaid chuck, said slip joint connections each coinprising a cam the pitch of the cam of one relatively to the pitch of the cam ot the other causing said piston on 'one stroke to rotate in the same directioiY as that in which said chuck rotates but without said piston enforcing rotation o'lsaid chuck and on the nent stroke said piston to enforce rotation of said chuck after imparting its energy of rotation to said chuck.

1i. ln a drilling machine, a casing, a re- .ciprocatory piston iii said casing having a hammer bar provided With straight and helical grooves lying side by'side, a chuck in said casing having a slip connection with said helical groove, ratchet teeth 'formed on the exterior ot the rear end oi said chuck,

Y rino' surrounding said hammer bar and abutting the rear end of said chuck, said ring having a slip connection with said straight groove, pawls cooperat'ng with the ra'L teeth on said chuck and ring toi' perini rotation of said ring and chui-,k irl-but and the same direction, wh on one stroke said piston imparts i said chuck Without itself rotating and on the subsequent stroke said piston rotates in the one same direction as that. in which it has Vini-- parted rotation to said chuck. Y

5. In a drilling machine, a drill steel, a casing, a reciprocatory piston in saidv ce g having a hammer bar provided with straight and helical grooves 'lying side by side, a chuck carrying saidY drill steel rotataaly mounted in said casing and having a slip connectionivith said helical groove, a ring surrounding said hammer bar rearwardly of said chuck and having a slip connection with said straigl'it groove, and means for permitting said rinO to rotate in but one direction,

whereby on one stroke said piston imparts rotation to said chuck without itself rotating and on the subsequent stroke said piston rotates in the saniedirection as that in Which it has imparted rotation to said chuck.

6. ln a drilling machine, a casing,a drill steel, a chuck rotatably mounted in said cas-- ing and carrying said drill steel, a piston in said casing and having a hammer bar,

helical grooves on said hammer barin engagement with cooperating lugs on said chuck, an angularly moving member, means Vpermitting said member to rotatein but one posed between l et c rotates chuck, an angularly movable member disposed between said cylinder and chuck` means providing a slip connection between said hammer bar and said member, means providing a slip connection between said hammer bar and` said chuc; and including a cam surface obiique to the axis of the piston and hammer bar, and means permitting rotation oi" said member and hammerbar in only one and the saine direction and preventing rotation thereof in the opposite direc tion, whereby said piston on one stroke rotates Without rotating said chuck and on its stroke in the opposite direction Without itself rotating causes's'aid chuck to rotate inv the same direction as that in which said piston rotated ou the preceding stroke.

8. ln a drilling machine, a cylinder, "a piston therein having a hammer bar, a chuck, an angularly movableimember dissaid cylinder and chuck, means providing a slip connection between said hammer bar and said member, means providing a'slip connection between said hammer bar and said chuck and including a cam surface oblique to the axis of ther piston and hammer ban-and separate means perini ng rotation of said member and hammer bar iii only one and the same direcrtion and preventing.rotation in the opposite direction, whereby said piston on one stroke fithout rotating said chuck and on its stroke in the opposite direction causes said chuck to rotate. Y Y

E). In a drilling machine, a cylinder7 a piston vtherein having a hammer bar, a ratchet ring surrounding` saidhammer bar, a chuck receiving said hammer,` bar, straight grooves on said hammer bar cooperating With said ring, helical Vgrooves on said hammer bar cooperating with said chuck, ratchet teeth on said chuck, and pawls cooperating with said ring andchuck ratchet teeth for preventing rotation of said ring and chuck iii one direction, whereby ou one stroke said piston imparts rotation to said chuck in one direction Without itself rotating and on the subsequent stroke said piston rotates in the same direction as that in which said chuck is rotated.

l0. In a drilling machine, a cylinder, :front and rear head structures therefor, side bolts providing a common means engaging both head 'structures and extending the length or' said cylinder for securing saidY head structures to said cylinder, a drill steel, means 'for rotating said steel comprising a ratcheL and a pawl cooperating With said ratchet and surrounding one of said side bolts.

a pawl, means for retaining said steel in operative relation to said piston to have imparted thereto such percussion and to be rotated,'and a bolt providing a common means tor directly holding said cylinder', said head structure, said paivl and said means for re taining the steel in assembled relation.

l2. In a drillingl machine, a cylinder, a head structure therefor7 a drill steel, a piston for imparting percussion to said steel, mechanism operated by said piston for rotating said steel, means for retaining said steel in operative relation to said piston to have imparted thereto such percussion and to be rotated, a bolt for directly holding said cylinder, said head structure7 and said means for retaining the steel in assembled relation, and a paivl cooperating With said mechanism and surrounding said bolt.

13. In a rock drill, a cylinder, a rear head structure, a chuck, a chuck casing, a drill steel carried by said chuck, a hammer piston in said cylinder for operating said steel7 mechanism operated by said piston for rotating said chuck and steel including a ratchet and pawl, a retainer tor holding said steel in said chuck against the action of said piston, bolts extending the length of said cylinder for holding said rear head and chuck casing in assembled relation with said cylinder, said pawl surrounding one of said bolts7 said bolts having heads in the form eyes adjacent said chuck casing, and said retainer being pivotally carried in said eyes.

In testimony whereof, I have signed my name to this specification.

GEORGE H. GILMAN.V 

